HELP! I have the answer to all 3 i just need to show my work. just a little confused please I'll add more points because its 3.​

Question 3 of 30 paul buys fruit to make smoothies. he buys 3.78 pounds of apples, 2.12 pounds of peaches, and 4.45 pounds of oranges. paul rounds each weight to the nearest tenth of a pound. about how many pounds of fruit did paul buy? (a) 10.5 pounds (b) 10.2 pounds (c) 10.4 pounds (d) 10.0 pounds 30 points

The data in the table represent the height of an object over time. which model best represents the data? height of an object time (seconds) height (feet) 05 1 50 2 70 3 48 quadratic, because the height of the object increases or decreases with a multiplicative rate of change quadratic, because the height increases and then decreases exponential, because the height of the object increases or decreases with a multiplicative rate of change exponential, because the height increases and then decreases

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.